The group of muscles that run down the back of your thigh are all part of your hamstrings. Any time you have an activity that requires sprinting with many sudden starts and stops, a hamstring injury is possible. Sports like soccer, baseball, or tennis can have a higher risk of a hamstring pull or strain.

The femur or the thigh bone is the longest and strongest bone in the body. It is so strong that archaeologists have found femur bones dating to 10000 years ago. They support the weight of the body and prevent all the stress from falling on the legs and the feet. They are made in such a way that they can withstand a huge amount of stress.